TAS5756M: Programming to use 3-wires slave mode

Part Number: TAS5756M

Hi - I'm trying to use TAS5754 in slave mode, 3 wires (SCLK, DO, LS). My system sends the right I2S data, I've verifed it with another DAC, but it remains silent on the TAS5754, nothing on the DAC_OUT. I'v not programmed any register, I was hoping that default configuration would work with 3-wires slave, but maybe it does not and the datasheet is not fully clear, especially page 67 says:

8.4.2.9 P0-R13

PLL Reference [6:4] (R/W) 00000000
This bit select the source clock for internal PLL. This bit is ignored and overriden in clock auto set mode.
The PLL reference clock is MCLK - 0 0 0 - - - -
The PLL reference clock is MCLK - 0 0 1- - - -
Reserved - 1 0 0 - - - -
The PLL reference clock is GPIO (selected using P0-R18) - 1 1 1 - - - -

Does somebody know what is the right register configuration for 3-wires slave mode and if the default could work?

Thanks